First off I should say 1.0 is really just a number. People get
confused about what 1.0 means sometime. It doesn't mean anything
except it does mean 10 really solid releases. That's something.
1.0 does not mean we are changing the API, or that you shouldn't use
this release because it's any different than 0.9. It is the same way
to 0.9 as 0.8 was to 0.7. 2.0 will just be 1.3 more. Numbers do not
mean anything to Ansible releases. We just go up 0.1 each time 
The changelog contains the full scope but you should also read the
writeup here: http://michaeldehaan.net/post/42070248518/ansible-1-0-released
Thank you EVERYONE for making this project rock so incredibly much,
and so fun to be a part of.
We have seen 10,000 unique visitors reading about Ansible this month,
won Black Duck's "2012 Rookie of the Year" software award, and just
passed 1000 "stars" on github in less than a year. This is your
success. Be proud of it. We are making waves.
1.1 is going to be big too, as I've promised to finally do basic
limited dry run support and I imagine I'm going to be suprised like
crazy from all the good ideas coming in. I won't promise anything
else, we'll just see where it goes.
BTW, tarballs had to move since github doesn't allow arbitrary file
uploads anymore, see http://ansible.cc/releases/ for those.
We'll likely continue our 2 month release cycle for the next release
as that seemed to agree with everyone in the survey.
For those running the latest git all the time, I've already bumped the
version info to say "1.1"
Note that I have NOT yet updated the release to include the docs for
all 1.1 features. I am going to do this before I make any other
feature commits, so look for this in the next few days, and I'll post
here about those and highlight the key sections.
As noted in the blog post, release 1.0 was "Eruption". Release 1.1
will be "Mean Street".
--Michael